This invention relates generally to aircraft flight data collection and more particularly to collecting flight data at increased sampling rates.
Modem aircraft currently operated by commercial airlines typically employ an onboard data acquisition system for collecting digital flight data. In such systems, a number of sensors distributed throughout the aircraft provide data signals representative of the performance of the aircraft and its engines. This flight data is stored in an attendant, physically robust flight data recorder (commonly referred to as the xe2x80x9cblack boxxe2x80x9d), so that in the unlikely event of an in-flight mishap, the flight data recorder can be removed and the stored flight performance data can be analyzed to determine the cause of the mishap. The stored flight data can also be used proactively in diagnostic maintenance of in-flight anomalies.
Flight data recorders collect a predefined set of data parameters at a fixed sampling rate throughout the entire flight. However, many aircraft or engine anomalies require data collected at higher sampling rates to understand and diagnose the problem. Unfortunately, the sampling rate and the number of data parameters that can be collected are limited by the capacity of the recorder""s storage medium and the expected duration of the flight, and the storage capacity is limited by physical constraints. In other words, for a given set of data parameters, the sampling rate must be set sufficiently low so that the recorder""s storage medium will not be consumed before the flight is completed.
Higher sampling rates are generally available on modem, digital aircraft through the use of digital flight data acquisition units (DFDAUs) or data management units (DMUs). While higher sampling rate data is available, the problem becomes one of storing large amounts of data, particularly over many flights. Thus, most data storage devices like quick access recorders (QARs) are limited to recording data at a fixed, relatively low rate. Another known storage device is the data storage unit in a wireless data link. A wireless data link is essentially a system in which flight data collected during a flight is stored in the data storage unit. When the aircraft lands, the flight data is downloaded via a wireless link to a flight control center computer located at the airport. These devices typically collect data at a fixed sampling rate that is limited by the capacity of the data storage medium.
Accordingly, there is a need for method and system for collecting flight data that can increase the sampling rate and the number of data parameters collected without consuming the available data storage capacity before the flight ends.
The above-mentioned need is met by the present invention which provides a method and system for collecting flight data from an aircraft in which an operational condition of the aircraft, such as the flight phase, is determined. Then, the data is collected at a first sampling rate when the flight phase is one of a first set of flight phases and collected at a second sampling rate when the flight phase is one of a second set of flight phases. The second sampling rate is greater than the first sampling rate.
The present invention and its advantages over the prior art will become apparent upon reading the following detailed description and the appended claims with reference to the accompanying drawings.